Cable clamp and apparatuses for attaching and for detaching the clamp

ABSTRACT

A releasable and lockably closing cable clamp has two clamp elements movable relative to each other between a release position and a cable-clamping closed position, and has a latch member movable between an unlatch position where the clamp elements are free for said relative movement and a latch position where it locks the clamp elements in the closed position. An attacher of the clamp to a moving cable has a carriage for moving a clamp with the cable into engagement with a clampclosing cam that closes the clamp onto the moving cable, and into engagement with a clamp-locking cam that moves the clamp latch element to the latch position. A detacher for releasing the clamp from a moving cable has an aligner that selectively orients the cable-carried clamp and feeds it to a guide passage. A follower engages the clamp in this passage and is moved by the advancing clamp to move a latchreleasing member to shift the latch member on the moving clamp from the latch position to the unlatch position, thereby allowing the two clamp elements to separate from each other and release the cable.

United States Patent Sept. 12, 1972 Whipple et al.

[54] CABLE CLAMP AND APPARATUSES FOR ATTACHING AND FOR DETACHING THE CLAMP [.72] Inventors: William D. Whipple; Howard W. Gifford, both of Westport Point,

Mass.

[73] Assignee: Prelude Corporation, Westport Point, Mass.

[22] Filed: NOV. 2, 1970 21 Appl. No.2 86,088

[52] US. Cl. ..29/200 D [51] Int. Cl. ..B23p 19/04 [58] Field of Search.....29/200 D, 200 P, 200 R, 452, 29/200 B [5 6] References Cited UNITED STATES PATENTS 3,098,289 7/1963 Demlerm, ..29/203 H 3,368,267 2/1968 Hedberg ..29/203 H Primary Examiner-Thomas l-l. Eager Att0meyl(enway, J enney & l-lildreth [57] ABSTRACT A releasable and lockably closing cableclamp has two clamp elements movable relative to each other between a release position and a cable-clamping closed position, and has a latch member movable between an unlatch position where the clamp elements are free for said relative movement and a latch position where it locks the clamp elements in the closed position.

An attacher of the clamp to amoving cable has a carriage for moving a clamp with the cable into engagement with a clamp-closing cam that closes the clamp onto the moving cable, and into engagement with a clamp-locking cam that moves the clamp latch element to the latch position.

A detacher for releasing the clamp from a moving cable has an aligner that selectively orients the cablecarried clamp and feeds it to a guide passage. A follower engages the clamp in this passage and'is moved by the advancing clamp to move a latch-releasing member to shift the latch member on the moving clamp from the latch position to the unlatch position, thereby allowing the two clamp elements to separate from each other and release the cable.

13 Claims, 16 Drawing Figures PATENTEDsEmmz V 131689.974

sum 1 or 9 Km/(C4 ATTORNEYS PATENTEI] SEP 12 I972 SHEET 2 OF 9 I ii. i..

INVENTORS WILLIAM D. WHIPPLE BY HOWARD W. GIFFORD M, M

ATTORNEYS PATENTED SEP 12 1912 SHEET 3 BF 9 lOOb IOO

FIG. 7A

PATENTEDSEP 12 I972 saw u or 9 INVENTORS WlLLIAM D. WHIPPLE HOWARD w. GIFFORD ATTORNEYS PATENTEDSEHMR 1689.974

sum 5 BF 9 FIG. 8

FIGS

INVENTORS WILLIAM D. WHIPPLE Y HOWARD W. GIFFORD ATTORNEYS PATENTEDsEPm m2 3.689.974

sum 6 or 9 FIG. I0

INVENTORS WILLIAM D. WHIPPLE H8 /HOWARD W. GIFFORD ATTORNEYS PATENTED SEP 12 m2 SHEET 7 0F 9 III l lk 3.689374 SHEET 8' or 9 PATENTEDSEP 12 m2 3 o m. oE

1NVENTORS WILLIAM D. WHIPPLE BY HOWARD W. GIFFORD M/ M ATTORNEYS PATENTEDsEP 12 I972 3,689,974

sum 9 or 9 INVENTORS WILLIAM D. WHIPPLE HOWARD W. GIFFORD YW/M 4/ ATTORNEYS CABLE CLAMP AND APPARATUSES FOR ATTACHING AND FOR DETACHING THE CLAMP BACKGROUND This invention relates to a clamp releasable from, and lockably attachable to, a moving cable by an automatic mechanism; and to clamp-attaching and clampdetaching equipments for use with the clamp.

The invention is advantageously used, for example, in the attachment of marine life-harvesting devices to atrawl cable. For this use, the clamp attaches harvesting devices, such as lobstertraps, at intervals to the trawl cable. The attacher affixes the clamps, with the traps hung from them, in succession to the trawl cable as it is payed out from a surface vessel for setting out the traps. When the trawl cable is hauled to empty the traps, the detacher releases the clamps automatically as the cable is hauled in.

As used herein, the term cable is intended to include all forms of lines, including ropes and cables of natural, synthetic and metal strands. The invention can also be practiced with chains, i.e. cables made of links. I

An object of the invention is to provide improved apparatus for removably attaching, and for detaching, articles relative to a moving cable. A more particular object is to provide such apparatus for use with a marine trawl cable to which articles are attached for setting out the trawl and from which the articles are removed when the trawl is hauled in.

Another object of the invention is to provide a clamp releasable from, and alternatively lockably attachable to, a moving cable by automatic mechanisms.

A further object of the invention is to provide a clamp of the above character capable of being detached automatically from the cable from either of two orientations relative to the cable.

It is also an object of the invention to provide a clamp of the above character which can be sheaved with the cable.

Another object of the invention is to provide apparatus for automatically detaching a clamp from a moving cable.

A further object is to provide suchclamp-detaching apparatus that requires no power source, but rather operates under actuation by the moving cable.

It is also an object to provide detaching apparatus of the above character for releasing from a moving cable a clamp having either of two orientations relative to the cable. v

A further object of the invention is to provide apparatus for attaching automatically a'clamp to a moving cable.

Another object is to provide clamp-attaching apparatus of the above character for affixing a succession of clamps to a moving cable at intervals along the cable.

It is also an object of the invention to provide apparatuses of the above character which are simple in construction and operation and hence are reliable and readily ruggedly constructed.

Another object is to provide such apparatuses capable of manufacture at a relatively low cost.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

2 GENERAL DESCRIPTION The deep-water, e.g. 100 fathoms-or more, trapping of lobsters becomes increasingly economical as the operation can be automated, particularly with relatively high-speed equipment that operates reliably and continually even in heavy seas.

The invention provides equipment for this and like purposes in the form, first, of a clamp for securing a lobster trap or other marine life-harvesting article to a trawl cable with a non-slip engagement. The clamp is constructed for automatic attachment to the cable while the cable is moving, as during the setting out of the trap-carrying trawl cable. The clamp further can automatically be releasedfrom the cable while the cable is being hauled in, with the. traps suspended from it. The clamp can pass over a pulley or like cable-guiding wheel with the cable. I

In one embodiment of the invention, a clamp for attachment to a cable extending along a third axis orthogonal to first and second orthogonal axes, has two clamp elements movable relative to each other along the first axis between a release position and a cableclamping closed position, and has a latch member movable along the second axis between an unlatch position .wherethe clamp elements are free for said relative movement and a latch position where it locks I the clamp elements in the closed position. The clamp is rugged, but yet is readily closed, locked, and released with automatic mechanisms.

An attacher of the clamp to a cable moving along the third axis has a carriage for moving a clamp along with the cable into engagement with a clamp closing cam that closes the clamp elements onto the moving cable. The carriage carries the closed clamp further, into engagement with a clamp-locking cam that moves the clamp latch element on the cam-closed clamp to the latch position. The attacher holds the clamp against movement along the third axis independent of the carria ge until the clamp is closed and locked to the moving cable. r

A detacher for releasing the clamp from a moving cable has an aligner that orients the cable-carried clamp along'the first and third axes and feeds it to a guide passage so that the clamp moves along a known path. Along this path, a follower engages the cable-carried clamp and is moved by it to move a latch-releasing member into the path to shift the latch member on the moving clamp from the latch position to the unlatch position. This allows the two clamp elements to separate from each other and thereby release the cable.

The invention accordingly comprises the features of construction, combinations of elements and arrangements of parts exemplified in the constructions hereinafter set forth, and the scope of the invention is indicated in the claims. I

BRIEF DESCRIPTION OF DRAWINGS For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description, taken in connection with the accompanying drawings, in which:

FIG. 1 illustrates deep-sea lobster trapping apparatus employing features of the invention;

FIG. 2 is a side elevation view, partly cut away, of a cable clamp according to the invention;

FIG. 3 is a top plan view of the clamp of FIG. 2;

FIG. 4 is a side elevation view of the clamp of FIG. 2 from the other side thereof;

FIG. Sis an end view of the clamp of FIG. 2, partly broken away;

FIG. 6 is a top plan view of a clamp aligner for use with a clamp detacher according to the invention;

FIGS. 7A and 7B are, respectively, a sectional side elevation view of the aligner of FIG. 6 along line 7A-7A thereof, and an end elevation view thereof;

FIGS. 8, 9 and 10 are, respectively, partly broken away top plan, side elevation, and end elevation views of a clamp detacher according to the invention;

FIGS. 11 and 12 are, respectively, foreshortened top plan and side elevation views of a clamp attacher according to the invention; and

FIGS. 13, 14 and 15 are sectional views of the attacher of FIGS. 11 and 12 taken along lines l3'-13, 14-14 and 15-15 respectively of FIG. 12 and showing successive stages during the operation of the attacher. 5

DESCRIPTION OF ILLUSTRATED EMBODIMENT FIG. 1 shows a marine surface vessel 10 hauling a marine trawl line or cable 12 having lobster traps 14 suspended from it at intervals along its length by means of secondary lines 16 which herein are termed gangion lines. A releasable clamp 24 is secured to one end of each gangion line 16 and releasably secures the gangion line and associated trap to the cable 12 with a nonslipping engagement.

The assemblage of the cable 12 and gangion lines 16 suspending traps 14 from it by way of the Clamps 24 is sometimes referred to herein as a trap trawl or a harvesting trawl.

A support 26 mounts a forward gangion block 30 over the side of the vessel 10, and a support 32 mounts a second gangion block 34 above and aft of the forward gangion block. A clamp-detaching unit 36 and power block unit 37 are successively in line with the trawl cable 12 past the second gangion block 34. In addition, a slide platform 38 for carrying traps 14 extends along the side of the vessel rearward from a forward loading end below the second gangion block 34.

In operation, after the buoy and anchor (not shown) at the starting end of the trawl cable are hauled aboard, the power block unit 37 commences hauling in the cable 12, drawing it first through the forward gangion block 30, then successively through the second gangion block 34 and through the detacher unit 36.'I-Iauled line from the power block unit is fed into a bin '40. Passage ofthe line 12 through the block 30 raises the linefrom the ocean bottom and lifts it from the water, with the gangion lines 16 and the traps 14 hanging from it. Each gangion block 30 and 34 preferably is constructed with a pair of sheaves forming a peripherally-grooved and axially-split wheel that supports the large diameter trawl cable 12 but leaves the gangion lines 16 free to pass through the gangion block suspended from the cable. (U.S. Pat. No. 587,839 discloses a rudimentary construction for the gangion blocks.) An idler sheave 41 depresses the line 12 slightly as it passes out of the gangion block 30 and on to the second gangion block 34, which further raises the trawl cable 12 to lift the traps l4 suspended from it onto the load end of the platform 38. As the line is hauled in from the second gangion block to the detacher unit 36, the traps slide with it rearward along the platform 38.

The detaching unit 36 automatically releases each clamp 24, allowing it to be removed from the advancing trawl cable 12 and thereby enabling the clamp together with the gangion line 16 and trap 14 connected to it to be removed from the trawl cable prior to entry of the cable into the power block unit 37.

Thus, as shown in FIG. 1, the gangion blocks 30 and 34 raise the trawl line 12, and guide it onto the vessel 10, and automatically separate the trawl line from the structure suspended from it. The detaching unit 36 disconnects this structure from the trawl line so that a conventional power block unit 37, or a winch, can continuously haul in the trawl cable. 'After passage of the trawl cable through the detaching unit 36, the traps 14 with the gangion lines 16 and clamps 24 attached to them are free for processing on the vessel 10 independent and separate from the cable.

With further reference to FIG. 1, the vessel 10 also has a clamp attacher 42 located aft of the foregoing trawl-hauling equipment and for attaching traps 14 to the trawl cable 12 during the setting out of the trawl. During the setting operation, the cable 12 indicated with dashed lines is fed from the bin 40 over guide sheaves 44 to the attacher, and then over the stern of the vessel 10. Traps 14 to be attached to the cable are loaded onto the platform 38 below the forward end of the attacher and the clamps 24 attached to them are placed on a rail in the attacher. As selected lengths of the cable 12 pass through the attacher 42, the attacher is operated to close a clamp onto the moving cable and lock it, thereby securing the clamp to the cable. The cable then carries the clamp with it, sliding the trap 14 suspended from the clamp, by way of a gangion line 16, rearward along the platform 38 and off to the water as indicated at the left side of FIG. 1.

A detailed construction of the clamp 24 and for the detacher unit 36 and attacher 42 as provided by the invention will now be described for use in the foregoing marine life-harvesting and like applications.

FIGS. 2 through 5 show the clamp 24; the clamp has an open position as shown in FIG. 4 and in phantom in FIGS. 2 and 5, and has a closed position shown with solid lines in FIGS. 2 and 5. The clamp has three basic parts, two clamp elements termed a clamp body 46 and a clamp jaw 48, and a latch element in the form of a latch pin 50. The clamp jaw 48 is movable relative to the clamp body 46 between the open and closed positions along a first, normally vertical axis and the latch pin is movable between latch and unlatch positions along a second, normally horizontal axis orthogonal to both the first axis and to a third, normally horizontal axis along which the cable to which the clamp is secured extends.

The clamp body 46 has a top-wall portion 52 and two side-wall portions 54 and 56 that depend from the topwall portion opposite each other to form together a channel for receiving, when the clamp is closed, part of the clamp jaw with the cable clamped between these clamp elements. Two wedge-like projections 59 depend from the top-wall portion within the channel between the side wall portions, on either side of a projection-free space in the channel. Grooved lower surfaces of these projections and the projection-free inside the latch pin 50. The two holes 64 and 66 are concentric parallel to thesecond axis and centered along the length of the clamp body, i.e. along the dimension parallel to the aforementioned third axis.

As indicated in phantom in FIG. 5, in the unlatch position, the latch pin 50 is removed from the wall portion 54 hole 64 and is seated only in the wall portion 56. However in the latch position, as indicated with solid lines in FIG. 5, the latch pin 50 is seated in both wall portion holes 64 and 66. The wall portion hole 64 thus provides a shoulder or latch surface accessible from within the'channel of the clamp body, i.e. from the side of wall portion 54 which faces the wall portion 56, for engaging the underside of the latch pin 50 when it is in the latch position. The hole 66 forms a similar latch surface, but partly cut away as described below.

The wall portion 54, as shown in FIGS. 2, 3 and 5, has two clamp hangers 68 protruding therefrom along the clamp width, i.e. along the second axis, adjacent the top-most bearing surface 60 of the clamp body. The hangers 68 fit onto a rail in the clamp attacher 42 of FIG. 1 for hanging the clamp therein free to travel with the cable 12 along the third axis. The hangers 68 purposefully protrude on the clamp body to provide outer side surfaces 680 by which the clamp can be guided, and they provide outer end surfaces 68b for actuating the clamp detacher.

The other clamp body wall portion 56 has a pair of abutments 70 protruding from it opposite the cable hangers 68 but spaced below the hangers. The outer side abutment surfaces 70a are used to guide the. clamp and the abutment outer end surface 70b come into play in the clamp attacher mechanism.

The two clamp body side-wall portions 54 and 56 also have similar and symmetrically located curved and rounded bumpers 54a and 56a, respectively. The bumpers 54a are at the lower corners of the shorter wall portion 54, and the bumpers 560 are at similarly located corners of the wall portion 56 and which are on either side of an extension 72 of this wall portion.

The extension 72 depends along the first axis, illustratively well beyond the wall portion 54 by several times the width of the clamp body channel and is apertured with a slot 74 extending down from the hole 66 but with a width less than the hole diameter. This slot forms a slide track to which the clamp jaw is secured, by way of the latch pin50, to the clamp body and along which the clamp jaw slides between the clamp open position and the clamp closed position. As shown in FIG. 5, the outer side of the extension 72 has raised camming ridges 76 on either side of the slot 74 and extending along the central portion of the extension 72 and tapered at both ridge ends. These camming ridges 76 draw the clamp jaw 48 against the extension as the jaw and body are moved together to the closed position.

With further reference to FIGS. .2, 4, and 5, the clamp jaw 48 has a channeled head 78 above two side arms 80 and 82 that together form a cable-engaging clamp surface 84 contoured roughly to mate, when the clamp is closed, with the clamp surface 58 of the clamp body 46. Specifically, when the clamp is closed, the head of the clamp jaw 48 fits into the clamp body channel between the two projections 59, 59 and the jaw arms 80 and 82 are closely beneath these projections. With this arrangement, the two clamp surfaces 58 and 84 of the closed clamp deform the cable 12 upward over the jaw head and, on either side of this upward bend, downward and around the two clamp body pro-' jections. This tortuous deformation of the cable 12 by closed clamp securely traps. the cable between the two clamp elements so that it can not become disengaged from them so long as the clamp remains closed.

As shown in FIGS. 2 and 5, the clamp jaw has a step 86 protruding laterally therefrom below the head 78 and centered between the two side arms 80 and 82. The lower surface of the step 86 forms a bearing surface 88 at which the jaw can be engaged for moving it from the open position upward into the clamp body to the closed position.

Between the head 78 and step 86 on the clamp jaw, a hole 90 extends through the jaw parallel to the second axis. A spring pin 92 traps the latch pin 50 in the jaw hole 90. The latch pin has cylindrical end portions 50a and 50b and a central portion 500 of reduced width (along the third axis) and with a bottom surface recessed with two axially spaced detents 50d and 50e. As shown in FIG. 5, in the unlatch position, thelatch pin 50 is seated with the detent 50d engaging the spring pin 92. The latch pin is moved sideways, along the second axis, from this-unlatch position to the left as shown in FIG. 5 to the latch position, where it is disposed with the detent Stle seated on the spring pin 92. Further, in the closed position of the latch, the jaw hole 90 is aligned with the clamp body hole 64 and the latch pin cylindrical end portion 50a is seated in this hole. The other end portion 50b of the latch pin is seated within the hole 66 of the clamp body. In the unlatch position of the latch pin 50, the end portion 50a is withdrawn from the body hole 64 to be in the space between the two clamp body side-wall portions 54 and 56, and the pin end portion 50b is likewise'removed from the hole 66 to protrude laterally from the clamp body, outside the side-wall portion 56.

Further, the slot 74 in the latch jaw 48 is of a width to slidably receive the flattened pin central portion 50c, but is too narrow to accommodate the pin end portion 5011. With this construction, when the latch pin is in the latch position as indicated in FIG. 5, the bottom of the hole 64 in the clamp body engages the pin end portion 50a and the wall of the hole 66 on either side of the slot 74 engages the other pin end portion 50b to hold the pin up in the latch-closed position and thereby to lock the latch closed.

Alternatively, when the latch is in the unlatch position, as indicated in phantom in FIG. the two pin end portions 50a and 50b are removed out of the body holes 64 and 66 and only the pin central portion 50c is engaged by the latch elements, being engaged within the hole 90 of the clamp jaw and passing through the slot 74 of the clamp body. The latch elements are then free to move apart to the open positionQ The large latch pin end portion 50b on the outside of the jaw slot, and the large pin end 50a on the far side therefrom of the jaw spring pin 92, hold the two latch elements together. Moreover, the engagement of the inner. shoulder on this pin end portion 50b, i.e. where it reduces in dimension to form the pin central portion 50c, with the jaw ridges 76 draws the jaw forward the clamp body extension 72 to ensure proper positioning of the jaw between the two body wall portions so it freely enters into the space between them during closure of the latch.

As shown in FIGS. 4 and 5, the clamp jaw 48 has a tongue 96 which protrudes on the jaw head into the clamp body slot 74, above the passage of the clamp pin 50 into the slot, when the clamp is not closed. The tongue stabilizes the position of the clamp jaw relative to the body, i.e. it restricts pivoting of the jaw about the latch pin 50, of the unclosed clamp. However, the tongue is essentially not restricted by the clamp body when the clamp is closed. This allows the jaw of the closed clamp to pivot on the pin 50 relative to the clamp body; the gangion line drag on the clamp jaw generally pivots the jaw in this manner. This pivoting of the jaw relative to the clamp body presses one jaw arm 80 or 82 harder into the clamped cable, thereby increasing the bite of the clamp onto the cable to ensure a non-slip engagement. v

With further reference to FIGS. 2, 4 and 5, the clamp jaw 48 has a tail 94 depending from the juncture of the jaw head 78 and jaw arms 80 and 82 to be roughly coextensive with the clamp body extension 72 when the two clamp elements are closed together. The lower, free end of the jaw tail 94 is arranged for attachment to whatever article the clamp is tosecure to the cable. The illustrated clamp has a U-shaped tail and a gangion line 16 is secured to the base of this U-shape.

One feature of the clamp tail is that it provides a moment arm between the clamp attachment to the gangion line and the center of the clamped cable. When the cable tends to rotate about its length, which would roll the clamp around the cable and thereby wrap the gangion line about the cable the pull of the trap-carrying gangion line at the end of this moment arm opposes this rolling of the clamps and hence resists the unwanted cable rotation.

The geometry of the clamp body 46 and jaw 48 as seen in FIGS. 2 and 4, with the top wall portion 52 elongated along the clamped cable and with the body extension 72 and jaw tail 94 depending from it, give the closed clamp 24 a roughly triangular or conical shape. This profile with an apex at the bottom facilitates passage of the clamp over the gangion blocks 30 and 34 of FIG. 1 and over other like wheel or sheave guides.

Turning to FIGS. 6 and 7, a clip aligner 98 is preferably used in conjunction with the clip detacher unit 36 of FIG. 1 to funnel each clamp 24 on the moving cable 12 into an upright orientation and into the proper alignment for passage through the detacher.

The aligner illustrated is an inverted chute with opposed side panels 99 and depending from a top panel 97. Each panel 99 and 100 has a forward section 99a, 1000 joined to a rear section 9%, 100b respectively which in turn joins to the detacher 36. The front edges of the forward sections are inclined downward from the vertical by approximately 45 and symmetrically flared apart, in the horizontal plane, illustratively by approximately 60 or slightly less, thereby forming a wide, downward-facing aperture for receiving the advancing clamp and moving it to an upright and aligned orientation. That is, for moving it into an orientation with the aforementioned first and third axes of the clamp respectively vertically and aligned along the vessel 10 length (FIG. 1). The top edges of the panel forward sections also are flared upward from the rear sections, the illustrated top edges are inclined 20 to 25 relative to the horizontal. The top edges of the panel rear sections have a lesser upward flare, e.g. 10 above the horizontal, and the bottom edges of the two panels are inclined downwardly from the detacher.

The side panel rear sections 99b, 10% are parallel to each other and each joins the corresponding front section along a bend generally parallel to the forward section front edge.

The clamp aligner 98 further hasa pair of conical sheave members 101 and 102, each of which is secured within the aligner chute to the inside of one panel section 99a and 100a, respectively. The sheave members are aligned along a common axis with their apexes facing each other and openly spaced apart to pass a clampcarried gangion line between them. The sheave members thus form a fixed (i.e. non-rotatable) gangion sheave within the aligner chute and locatedadjacent the bottom front comer, which is on the aligner outward from the detacher 36.

A pair of ramp-members 103 and 104 are affixed on opposite sides within the aligner chute to the panels 99 and 100, respectively. The ramp members are opposite each other and each forms a narrow ramp surface inclined upward from the gangion sheave to the detacher 36. I

With this construction of the aligner 98, as a cable advances into the aligner along arrow 105, the path of a taut cable, or arrow which indicates the path of a slack cable, the funneling and downwardly facing panel sections 99a and 1000 constrain a clamp on the cable to be upright and to pass over the closely-spaced gangion sheave members 101 and 102 with the gangion line suspending from it passing between the sheave members. Inside the aligner chute beyond the sleeve members, the clamp is free to drop down until the clamp bumpers 54a and 56a (FIGS. 2 and 4) ride on the ramp members 103 and 104, which are spaced apart to pass the clamp extension 72 and tail 94 (FIGS. 2 and 4) but to engage the bumpers. The advancing clamp then rides upwards on the aligner ramp members 103 and 104, and is aligned by sliding engagement of the clamp hangers 68, abutments 70 and bumpers along the panel rear sections 99b and 10%.

The aligner, and the detacher 36 now to be described with reference to FIGS. 8, 9 and 10 can receive and handle clamps carried on a cable advancing in the order of 1 ,000 feet per minute.

The detacher 36, shown in FIGS. 8, 9 and 10 moves the clamp latch pin 50 (FIGS. 2 through 5) from the aforementioned latch position to the unlatch position automatically as the advancing cable 12 carries the clamp through the detacher. A cast metal or like rugged housing 106 forms a three-sided throat 107 that receives the clamp from the aligner 98 and through which the clamp passes in the detacher. A succession of rollers 108 rotatably mounted in the housing forms a roller-conveyor upper surface 110 of the throat. This roller surface engages, and bears downward against, the upper bearing surface 60 of a clamp passing through the detacher.

The housing forms parallel throat side walls 112 and 114 that blend with the aligner panel rear sections. These side walls are spaced apart only slightly more than the maximum clamp width and engage a passing clamp from one side at the abutments 70 and bumpers 56a and from the other side along the outside of the hangers 68, the bumpers 54a and at the end of the step 86 (FIGS. 2through 5), for fixing the position of the passing clamp along the second axis, i.e. sideways relative to the direction of advance.

Each detacher side wall 112, 114 carries a wheel 116, 118 respectively protruding therefrom into the throat. The two wheels are rotatable about a common axis parallel to the aforementioned second axis, with each wheel having a spindle journaled to the housing in such manner that the space between the wheels is open and hence free for a clamp tail and extension to pass therethrough. The wheel rims 116a, 118a protruding into the detacher throat are frusto-conical, each with a greater radius adjacent the associated side wall than at its inner end further within the throat from that side wall. As shown in FIG. 10, this wheel rim surface mates with the clamp surface 88 on the under side of the protruding step 86 on the clamp jaw. Hence as a cable carries a clamp through the detacher throat, the step on the .clamp jaw engages the wheel on oneside of the detacher throat, and rolls upward on the wheel rim to press the clamp top bearing surface 60 against the roller conveyor surface 110 and thereby squeeze the clamp elements 46 and 48 together sufficiently to unload" the latch pin 50 from bearing surfaces of holes 64 and 66. This facilitates the shift of the latch pin to the unlatch position.

Ramp plates 120 and 122, one on each throat side wall ahead, i.e. to the left in FIGS. 8 and 9, of the wheels 116, 118 respectively, protrude into the throat as continuations of the aligner ramp members 103, 104 (FIGS. 6 and 7) to raise the moving latch upward to engage a wheel close to the top thereof. The ramp plates lift the clamp to engage the wheel within a few degrees of the vertical. The illustrated ramp plates are arranged, like the aligner ramp members, to engage a clamp along the underside of the bumpers 54a and 56a (FIGS. 2 through 5).

The detacher unlatches a clamp latch pin 50 with an unlatcher indicated generally at 121 and having two conjoined rotatable arms, one a clamp-follower arm 124 and the other a pin unlatching actuator arm 126. The two arms are fixed to a collar 128 from which they extend with a small angle, e.g. to between them. The collar is mounted to the housing 106 off to one side from the throat for rotation about an axis parallel to the first axis and centered close above or slightly beyond, as seen in FIG. 9, the high point of the wheel 1 16 below it. The follower arm 124 extends from the collar. 128 through a slot 130 in side wall 112 to protrude into the throat just below the roller surface 110, i.e. at the height of a hanger 68 on the clamp in the throat and urged upward on wheel 1 16.

The actuator arm 126 extends into the detacher throat from the collar 128 in a direction ahead, i.e. to enter the throat upstream from the follower arm 124, and below the follower arm 124 at the level of the latch pin 50 of a clamp passing through the detacher on the wheel 116. A slot 132 in the throat side 112 allows the actuator arm to enter the throat space.

A tension spring 134 is stretched between a pin 136 and a short apertured arm 138 fixed on the collar 128 to hold the unlatcher 121 in a normal retracted position shown in FIG. 8. In this retractedposition of the unlatcher, the free end of the actuator arm 126 is in the slot 132 withdrawn just outside the detacher throat, but the free end of the follower arm 124 extends through its associated slot 130 and protrudes into the throat, as

. shown in FIGS. 8 and 10.

When aclamp 24 advances through the detacher, just as it is carried upward on one of the wheels 116, 118 to bear against the roller surface 110, one hanger 68 on it moves against the end of the follower arm 124 in the throat and pushes the follower arm ahead of it along the throat, thereby rotating the unlatcher .121 counter-clockwise in FIG. 8. This rotation of the unlatcher swings the actuator arm 126 out from the slot 132 into the throat and, as the clamp continues to move through the throat, the actuator arm 126 is swung counter-clockwise and rapidly pushes the unloaded latch pin 50 to the unlatch position.

As soon as the clamp pushes beyond the unlatcher 121, the restoring spring 134, which is stretched by the rotation of the unlatcher, draws the unlatcher clockwise back to the normal retracted position of FIG.

The illustrated detacher 36 has a second unlatcher 140 identical to the unlatcher 121 and mounted on the housing 106 on the other side of the throat 107. As shown in FIG. 10, a clamp passing through the detacher engages only one wheel 116, 118 and only one of the two unlatchers 121, 140, depending on rotational posiu'on with which the clamp is clamped onto the cable 12, i.e. depending on which side the clamp step 86 and clamp hangers 68 face. Thus, the illustrated detacher 36 automatically detaches the clamps 24 from the cable 12 with no source of power other than the motion of the cable carrying the clamp.

With reference to FIG. 1, as the cable 12 is hauled on from the detacher 36 to the power block unit 37, the open clamps 24 can readily be removed from the cable manually. Thus, with the clamp 24 and detacher 36, used in conjunction with an aligner as shown in FIGS. 6 and 7, the lobster trawl can be hauled in continuously at a rapid rate, e.g. at least several hundred feet per minute, and the trawl cable 12 automatically separated from the traps 14 as well as from the gangion lines 16 and clamps by which the traps attach to the cable. The releasable but lockably closing clamps as thus provided by the invention, and the automatic detaching of them from the cable thus enablethe cable to be hauled in with conventional power block or winch equipment continuously and at a rapid rate.

FIGS. 11 through 15 show the clamp attacher 42 of FIG. 1, with FIGS. 13, 14 and 15 showing different stages of the attacher during its operation. The cable 12 enters the attacher free of clamps at an idler sheave 142 at the right side of FIGS. 11 and 12 and leaves the attacher, with clamps attached to it, guided by a gangion sheave 144. The sheaves 142 and 144 thus guide the cable through the attacher normally along a path 145 aligned between them.

The sheaves 142 and 144 are mounted on opposite ends of a carriage rail 146 that extends along a second,attacher .path skewed from the normal cable path at the rail end adjacent sheave 142 but essentially coinciding with it adjacent the gangion sheave 144. The carriage rail 146 carries a clamp rail 148 below it and which receives the two hangers 68, 68 of a clamp to carry the clamp along the attacher path.

A carriage indicated generally at 150 is mounted. on the carriage rail for movement along it, and hence along the attacher path, between a start location shown in FIGS. 11 and 12 and a finish location indicated at 152. The carriage 150 has a guide frame 154 that is captive on the carriage rail for mounting the carriage thereon. The guide frame carries the elements that hold a clamp in the attacher constrained to move along the attacher path only with the carriage until the clamp is closed and locked onto the cable.

As shown in FIG. 15, a plate 156 is pivotally mounted to the guide frame for limited rotation about the aforementioned first, vertical axis from a lock position. An edge 156a of the plate is angled relative to the attacher path and is disposed progressively protruding into the path so that a clamp slid (e.g. manually) along the clamp rail 148 to the start location from the right (FIGS. 11 and 12) thereof engages the plate edge, and pivots the plate in one direction from the lock position to pass by it to'become loaded in the attacher carriage. A'tension springl58 returns the plate to its pathprotruding lock position, where a forward edge of the plate bears against an abutment 70 on the clamp. The plate is fixed against rotation in the opposite direction and hence precludes the loaded clamp from moving relative to the carriage to the right in FIGS. 11 and 12.

A stop block 160 is pivotally mounted on the carriage guide frame 154 for limited rotation about an axis parallel to the aforementioned second, horizontal axis. As indicated in FIG. 12, the block has a rest position where it is in front (to the left in FIGS. 11 and 12) of an abutment 70 on a loaded clamp. In this position the stop block prevents the clamp from moving leftward relative to the carriage, and hence prevents the loaded clamp from being pulled out of the attacher by the moving cable before the clamp is closed and locked. A cam surface 162 (FIG. 11) lifts the stop block upward to release the clamp from it at the finish location of the attacher, and thereby frees the clamp to move out of the attacher with the cable.

After a clamp is loaded into the attacher carriage frame 154 and automatically locked by the plate 156 and block 169 against movement relative thereto, the attacher is operated to close and lock the clamp onto the cable by operating a hydraulic cylinder-piston actuator 164 to drive the carriage frame 150 along the rail from the start position shown to the finish position 152. The actuator piston is connected to the guide frame 154, and the cylinder is fixed to the carriage rail 146 adjacent the idler sheave 142.

To close and'lock a latch, the attacher has three cams affixed to the carriage rail 146, a cable-shifting cam 166, a clamp-closing cam 168 and a locking cam 170. The cable-shifting cam 166 extends along the rail 146 from adjacent the start position to the finish position. As shown in FIG. 11, it is offset to the side of the rail by a large distance at the start position, tapers in toward the rail just beyond that and then extends parallel to the rail. The cam 166 engages a follower bar 172 mounted to the top of the carriage guide frame 154 for rotation about a pivot axis 174 parallel to the carriage path.

As shown in FIGS. 12 and 15, the follower bar 172 extends downward from its pivot axis 174 between the rail 146 and cable-shifting cam 166 to below the cable 12. The bar passes outboard of the cable, i.e. on the side away from the carriage rail. A tension spring 176 resiliently urges the bar against the cam 166. When the actuator drives the carriage down the rail 146 from the start position, the engagement of the cable-shifting cam against the follower bar pivots the bar from a start position shown in solid lines in FIG. 15 into a cable shifting position indicated there with broken lines. This moves the bar laterally toward the carriage rail and causes it to shift the cable 12 from the normal path 145 to coincide with the carriage path, i.e. to lie below the carriage rail. In this shifted position, the cable is directly between the clamp surfaces 58 and 84 of the open clamp loaded in the carriage. The shifting cam 166 holds the bar 172 positioned to maintain the cable 12 along the carriage path during the rest of the carriage travel along the carriage rail.

As shown in FIGS. 11, 12 and 13, the carriage guide frame 154 carries a slide member 178 that the clampclosing cam 168 pushes upward to close the clamp as the guide frame 154 carries it along the rail 146. Specifically, the guide frame seats the slide member 178 between a pair of vertically extending dovetail surfaces 180, 180 above the carriage rail, and a tension spring 182 between the frame 154 and the slide member 178 biases the slide member in a downward rest position shown in FIG. 13. The slidemember, having dovetail surfaces mating within those of the guide frame, extends down and around the carriage rail to a foot 178a below the open jaw 48 on a loaded clamp 24. The slide member foot 1780, in the rest position, is directly below the step 86 of the open clamp in the attacher start position. j

Above the carriage rail, the slide member 178 carries a roller 184 rotatable about an axis 186 which is parallel to the second axis of the loaded clamp. This roller 184 rides on the clamp-closing cam 168, which is an upstanding plate with an upper camming surface having a start portion 168a that is close to and parallels the carriage rail 146 at the attacher start location and along the carriage rail to the point where the cableshifting earn 166 commences its extension close to and parallel to the rail 146. Adjacent this point, the surface which forms cam 168 inclines upward by the distance required to close the clamp. The cam 168 thereafter is flat, parallel to the carriage rail for a locking portion 1681). Beyond the locking portion, the surface of cam 168 drops slightly toward the carriage rail to an end, unloading portion 168C parallel to the carriage rail.

With this construction of the carriage slide member 178 and clamp-closing cam 168, when the carriage 150 carries a clamp along the rail 146, the slide member remains in the rest position of FIG. 13 during the carriage travel along the inwardly extending portion of the cable-shifting cam 166 and during which the cable 12 is shifted from the normal path to between the clamp elements 46 and 48. With further carriage travel, the roller 184 engages the incline portion of the earn 168 and rides upward therealong, drawing the slide member upward. The foot 178a of the rising slide member engages the clamp jaw step 86 and accordingly carries the jaw upward with it, thereby closing the clamp about the cable 12. t The slide member 178 remains up in the clampclosed position as the roller 184 thereon rides along the high flat portion 168b of cam 168. During this travel, the clamp latch pin is moved to lock the clamp in the manner discussed below. Thereafter, as the slide member drops down with the cam 168, it releases the locked clamp. This is the condition shown in FIG. 14.

As shown in FIGS. 11, 12 and 14, an arm 188 attached to the rail beyond the finish position 152 and extending parallel with it to adjacent the cam portion 168b has a surface 188a facing the rail 146 and roundly curving toward the rail from the free end of the arm. This surface, which extends along the rail at the clampclosing cam portion 168b, forms the locking cam 170. The latch pin 50 on a carriage-carried clamp thus engages this cam surface and is pressed to the latch position during the time the clamp is squeezedclosed by .the cam portion 168b engaging the roller of the carriage slide member 178.

The arm 188 can also have a further camming projection 190, to the right in FIG 12, for lifting the clamp latch pin to the horizontal, should it be inclined downward, prior to the engagement of the pin with the surface 1880 of cam 170.

The cam surface 1562 noted above for lifting the stop block 160 clear of the projections 70 on a clamp is also on arm 188. This cam surface forms a raised ramp on the top surface of the arm and is opposite the unload portion 1680 of the clamp-closing cam.

Thus, after the actuator 164 has driven the attacher carriage 150 the length of the rail 146 to the finish position, a clamp previously loaded into the attacher is closed and locked onto the cable, which has been shifted from its normal path to the attacher path. Further, the carriage releases the clamp, by withdrawing the slide member down to the position of FIG. 14 and by camming the stop block 160 away from the clamp. Accordingly, the clamp is free to be carried off the leftmost end of the clamp rail 148 and out of the attacher with the trawl cable 12. The gangion line suspended from the attached clamp passes through the gangion sheave 144 and, as shown at the right side of FIG. 1, the cable carries the clamp and gangion line and trap 14 over the stern of the vessel 10.

A switch 192 (FIG. 12) on the attacher is actuated by the arrival of the carriage at the finishposition. lt signals conventional control devices (not shown) to retract the actuator 164 to return the carriage back along the carriage rail to the start position.

It will thus'be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above descrip tion or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described the invention, what is claimed as new and secured by Letters Patent is:

1. Apparatus for the automatic unlatching of a clamp moving along a third axis orthogonal to first and second mutually orthogonal axes and having first and second clamp elements movable relative to each other along said first axis between a release position and a closed position and having a latch member movable along said second axis between an unlatch position where the clamp elements are-free for said relative movement and a latch position where the latch member secures said clamp elements in said closed position, said unlatching apparatus comprising:

A. guide means for receiving the clamp advancing along said third axis and for guiding it along guide v surfaces extending in planes parallel to said first and third axes and parallel to said second and third axes for further advancement along said third axis on a known path,

B. a first follower normally disposed in a retracted position where it protrudes at a first location into said path of the clamp advancing along said guide surfaces, and movable longitudinal to said third axis from said retracted position under engagement by the advancing clamp to a second location where it is out of said path, and

C. a first latch-release member linked to said follower and moved by said movement of said follower from a retracted position out of said path longitudinal tov said second direction into said path for, engaging the latch member of the advancing clamp and moving it to said unlatch position.

2. Automatic unlatching apparatus as defined in claim 1 further comprising cam means disposed proximal along said third axis to said latch-release member and for urging the advancing clarnp against a first guide surface parallel to said second and third axes and simultaneously urging said first and second clamp elements in the direction from said release position to said closed position to relieve the clamping load between them concurrent with the movement of said latch-release member in said second direction from said retracted position thereof.

3. Automatic unlatching apparatus as defined in claim 2 in which said cam means includes a circular member rotatable about an axis parallel to said second axis.

4. Automatic unlatching apparatus as defined in claim 2 in which said first guide surface includes a roller platform opposite, along said first axis, said cam means for passage of the advancing clamp between said roller platform and said cam means, said roller platform comprising plural rollers successively spaced along said third axis and each rotatable about an axis parallel to said second axis.

5. Automatic unlatching apparatus as defined in in claim 1 in which said follower includes an arm extendingin a plane parallel to said second and third axes froma first end disposed in said path to a second end mounted outside said path for rotation about an axis parallel to said first axis.

6. Automatic unlatching apparatus as defined in claim 1 further comprising restoring means resiliently urging said follower and said. latch-release member to said retracted positions thereof.

7. Automatic unlatching apparatus as defined in claim 1 in which said latch-release member includes an arm elongated in a plane parallel to said second and third axes and mounted at one end outside said path for rotation about an axis parallel to said first axis and with the other end out of said path in the retracted position thereof and movable with said rotation'thereof into and along said path.

8. Automatic unlatching apparatus as defined in claim 1 A. in which said first follower and first release member are disposed alongside said path, and

B. further comprising a second follower and a second latch-release member, each of which is disposed on the side of said path opposite said first follower and said first latch-release member, respectively.

9. Apparatus for the automatic unlatching of a clamp moving along a third axis orthogonal to first and second mutually orthogonal axes and having first and second clamp elements movable relative to each other along said first axis between a release position and a closed position and having a latch member movable along said second axis between an unlatch position where the clamp elements are free for said relative movement and a latch position where the latch member secures said clamp elements in said closed position, said unlatching apparatus comprising: I

A. guide means 1. having a first guide surface extending along said second and third axes,

2. having a pair of opposed second guide surfaces each of which extends along said first and third axes and together forming with said first guide surface a passage for guiding the advancing clamp along a known path longitudinal to said third axis,

B. a clamp unlatcher 1. having first and second arm members joined together at first ends thereof,

2. mounted for rotation of said arm members adjacent said first ends thereof about a common axis parallel to said first axis and in different planes parallel to said first guide surface,

3. having a retracted position where the other end of said first arm member extends into said path for engagement by a clamp advancing along said path and where the other end of said second arm member is out of said path,

4. rotatable about said common axis, from said retracted position, by the engagement of said first arm member with an advancing clamp to move said first arm member with the advancing clamp an to move t e othe end of said second arm mem r into sai path or moving the latch member of the advancing clamp to said unlatch position, and

C. restoring means for biasing said unlatcher into said retracted position thereof.

10. Unlatching apparatus as defined in claim 9 A. in which said first guide surface is parallel to the horizontal and said second guide surfaces are vertical,

B. further comprising an aligning chute in line with said guide means along said third axis for engaging the advancing clamp prior to entry into said guide passage and for orienting it with said first axis vertical and said second and third axes horizontal,

C. further comprising cam means for engaging the clamp advancing in said guide passage and for urging it against said first guide surface with the clamp elements thereof urged into said closed position, to relieve clamping stresses in the latch member, concurrent with the rotation of the unlatcher second arm member into said path. v

11. Apparatus for the automatic unlatching of a clamp moving along a third axis orthogonal to first and second orthogonal axes and having first and second clamp elements movable relative to each other in a direction transverse to said second axis between a release position and a closed position and having a latch member movable along said second axis between an unlatch position where the clamp elements are free for said relative movement and a latch position where the latch member secures said clamp elements in said closed position, said unlatching apparatus comprising:

A. guide means for receiving the clamp advancing along said third axis and for guiding it further along said third axis on a known path,

B. a first follower normally disposed in a retracted position where it protrudes at a first location into said path of the clamp and movable longitudinal to said third axis from said retracted position under engagement by the advancing clamp to a second location where it is out of said path, and

C. a first latch-release member moved in response to said movement of said follower from a retracted position out of said path longitudinal to said second axis into said path for engaging the latch member of the advancing clamp and moving it to saidunlatch position.

12. Automatic unlatching apparatus as defined in claim 11 further comprising cam means disposed proximal along said third axis to said latch-release member and urging said first and second clamp elements in the direction from said release position to said closed position to relieve the clamping load between them concurrent with the movement of said latch-release member in said second direction from said retracted position thereof.

13. Apparatus as defined in claim 12 in which said cam means includes a member rotatable about an axis parallel to said second axis and having a peripheral bearing surface extending circumferentially relative to said rotation axis, said bearing surface engaging said clamp during the engagement thereof with said latchrelease member. 

1. Apparatus for the automatic unlatching of a clamp moving along a third axis orthogonal to first and second mutually orthogonal axes and having first and second clamp elements movable relative to each other along said first axis between a release position and a closed position and having a latch member movable along said second axis between an unlatch position where the clamp elements are free for said relative movement and a latch position where the latch member secures said clamp elements in said closed position, said unlatching apparatus comprising: A. guide means for receiving the clamp advancing along said third axis and for guiding it along guide surfaces extending in planes parallel to said first and third axes and parallel to said second and third axes for further advancement along said third axis on a known path, B. a first follower normally disposed in a retracted position where it protrudes at a first location into said path of the clamp advancing along said guide surfaces, and movable longitudinal to said third axis from said retracted position under engagement by the advancing clamp to a second location where it is out of said path, and C. a first latch-release member linked to said follower and moved by said movement of said follower from a retracted position out of said path longitudinal to said second direction into said path for engaging the latch member of the advancing clamp and moving it to said unlatch position.
 2. Automatic unlatching apparatus as defined in claim 1 further comprising cam means disposed proximal along said third axis to said latch-release member and for urging the advancing clamp against a first guide surface parallel to said second and third axes and simultaneously urging said first and second clamp elements in the direction from said release position to said clOsed position to relieve the clamping load between them concurrent with the movement of said latch-release member in said second direction from said retracted position thereof.
 2. having a pair of opposed second guide surfaces each of which extends along said first and third axes and together forming with said first guide surface a passage for guiding the advancing clamp along a known path longitudinal to said third axis, B. a clamp unlatcher
 2. mounted for rotation of said arm members adjacent said first ends thereof about a common axis parallel to said first axis and in different planes parallel to said first guide surface,
 3. having a retracted position where the other end of said first arm member extends into said path for engagement by a clamp advancing along said path and where the other end of said second arm member is out of said path,
 3. Automatic unlatching apparatus as defined in claim 2 in which said cam means includes a circular member rotatable about an axis parallel to said second axis.
 4. Automatic unlatching apparatus as defined in claim 2 in which said first guide surface includes a roller platform opposite, along said first axis, said cam means for passage of the advancing clamp between said roller platform and said cam means, said roller platform comprising plural rollers successively spaced along said third axis and each rotatable about an axis parallel to said second axis.
 4. rotatable about said common axis, from said retracted position, by the engagement of said first arm member with an advancing clamp to move said first arm member with the advancing clamp and to move the other end of said second arm member into said path for moving the latch member of the advancing clamp to said unlatch position, and C. restoring means for biasing said unlatcher into said retracted position thereof.
 5. Automatic unlatching apparatus as defined in in claim 1 in which said follower includes an arm extending in a plane parallel to said second and third axes from a first end disposed in said path to a second end mounted outside said path for rotation about an axis parallel to said first axis.
 6. Automatic unlatching apparatus as defined in claim 1 further comprising restoring means resiliently urging said follower and said latch-release member to said retracted positions thereof.
 7. Automatic unlatching apparatus as defined in claim 1 in which said latch-release member includes an arm elongated in a plane parallel to said second and third axes and mounted at one end outside said path for rotation about an axis parallel to said first axis and with the other end out of said path in the retracted position thereof and movable with said rotation thereof into and along said path.
 8. Automatic unlatching apparatus as defined in claim 1 A. in which said first follower and first release member are disposed alongside said path, and B. further comprising a second follower and a second latch-release member, each of which is disposed on the side of said path opposite said first follower and said first latch-release member, respectively.
 9. Apparatus for the automatic unlatching of a clamp moving along a third axis orthogonal to first and second mutually orthogonal axes and having first and second clamp elements movable relative to each other along said first axis between a release position and a closed position and having a latch member movable along said second axis between an unlatch position where the clamp elements are free for said relative movement and a latch position where the latch member secures said clamp elements in said closed position, said unlatching apparatus comprising: A. guide means
 10. Unlatching apparatus as defined in claim 9 A. in which said first guide surface is parallel to the Horizontal and said second guide surfaces are vertical, B. further comprising an aligning chute in line with said guide means along said third axis for engaging the advancing clamp prior to entry into said guide passage and for orienting it with said first axis vertical and said second and third axes horizontal, C. further comprising cam means for engaging the clamp advancing in said guide passage and for urging it against said first guide surface with the clamp elements thereof urged into said closed position, to relieve clamping stresses in the latch member, concurrent with the rotation of the unlatcher second arm member into said path.
 11. Apparatus for the automatic unlatching of a clamp moving along a third axis orthogonal to first and second orthogonal axes and having first and second clamp elements movable relative to each other in a direction transverse to said second axis between a release position and a closed position and having a latch member movable along said second axis between an unlatch position where the clamp elements are free for said relative movement and a latch position where the latch member secures said clamp elements in said closed position, said unlatching apparatus comprising: A. guide means for receiving the clamp advancing along said third axis and for guiding it further along said third axis on a known path, B. a first follower normally disposed in a retracted position where it protrudes at a first location into said path of the clamp and movable longitudinal to said third axis from said retracted position under engagement by the advancing clamp to a second location where it is out of said path, and C. a first latch-release member moved in response to said movement of said follower from a retracted position out of said path longitudinal to said second axis into said path for engaging the latch member of the advancing clamp and moving it to said unlatch position.
 12. Automatic unlatching apparatus as defined in claim 11 further comprising cam means disposed proximal along said third axis to said latch-release member and urging said first and second clamp elements in the direction from said release position to said closed position to relieve the clamping load between them concurrent with the movement of said latch-release member in said second direction from said retracted position thereof.
 13. Apparatus as defined in claim 12 in which said cam means includes a member rotatable about an axis parallel to said second axis and having a peripheral bearing surface extending circumferentially relative to said rotation axis, said bearing surface engaging said clamp during the engagement thereof with said latch-release member. 